Gravity

From (The Plasma Universe Wikipedia-like Encyclopedia)

Gravity is a phenomenon through which all objects with mass attract each other. The force is proportional to the mass of the objects (ie. double the mass produces double the force), and inversely proportional to the square of the distance (ie. double the distance, produces four times less force).

Charged particles up to the size of small grains, may be more strongly influenced by electromagnetic forces than gravity. Gravity is always an attractive force, whereas electromagnetic forces may be attractive or repulsive. (See "Electromagnetic force" for a comparison between the electromagnetic and gravitational forces)

The physics of the influence of gravity and electromagnetic forces on a particle, is called "gravito-electrodynamics".